The present invention relates to a film for wiring, and a sputter target material for forming the film, wherein the film is applied to a flat panel display (hereinafter referred to as “FPD”) or the like, which is produced by forming a thin film on a substrate.
With regard to the FPD which is fabricated by laminating a thin film on a glass substrate or a silicon wafer, for example, various new products of the FPD have been keenly researched and developed in these days, which include liquid crystal displays (hereinafter referred to as “LCD”), plasma display panels (hereinafter referred to as “PDP”), field emission displays (hereinafter referred to as “FED”), electroluminescence displays (hereinafter referred to as “ELD”) and electronic papers.
There have been used transparent conductive films of ITO (Indium-Tin-Oxide) as the wiring film for the FPDs, optionally with display electrodes of ITO in the case where a high definition display is required, or other wiring films for the FPDs, which are made of a refractory metal of Cr, Mo or an alloy thereof having a low electrical resistance and being excellent in adhesiveness to substrates. Further, recently, there have been used lower resistance wiring films made of Al or Al alloy films under the background that liquid crystal TVs having a size of 15 inches require high speed driving in order to display moving images.
One defect of Al is poor in heat resistance property. When an Al film for wiring is heated in a manufacturing process of FPD or other various devices, there occur hillocks and/or whiskers caused by stress relief resulting in occurrence of short circuit or defects in protective films. Thus, it has been tried to restrain occurrence of hillocks and so on by various means of, for example, adding an alloying element to Al to make an Al alloy film, or coating an Al film with another metal film (see, for example, JP-2733006-B2 and JP-A-2001-350159.
On the other hand, with respect to displays for small portable devices and so on, hereafter, it will be needed to provide films for wiring which have lower electrical resistance and can be produced under a lower processing temperature, since there have been used resin substrates, resin films and so on in place of glass substrates, etc., in order to improve shock-resistance property and more lighten the devices.
Furthermore, in order to realize a high definition display such as a high definition TV with utilization of a big size LCD having a size of more than 30 or more than 50 inches or an organic ELD, and also improved high speed responsibility for moving images, a film for wiring having lower electrical resistance is required.